Wild celery, Cyclospermum leptophyllum, seeds.

Brown tan seeds with distinct dark brown ridges arranged randomly on a gray background. The seeds are small, with a scale marker indicating 1 millimeters. Copyright information is at the bottom (Copyright 2007 The Regents of the University of California. All rights reserved.). Credit: James A. O'Brien, University of California
Credit: James A. O'Brien, University of California